Old repositories (1 year-old+) like CenterNet are using PyTorch < 1.0.0, so DCN extension could not be built because of API change.
This repo contains useful replacement of DCN extension with torchvision function.
So you can install this module and replace such code:
from .DCNv2.dcn_v2 import DCN
to:
from dcn_v2_pytorch import DCNv2 as DCN
and models will work without diving in problems of extension compilation.
pip install git+https://github.com/lobanov-m/dcn-v2-pytorch.git
Repository requires pytorch >= 1.8.1 and torchvision >= 0.9.0
(in this version torchvision started to support modulated deformable convolutions).